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mfd: wm8350-i2c: Make sure the i2c regmap functions are compiled
[linux/fpc-iii.git] / net / netfilter / nfnetlink_log.c
blob09172d7abee2a0edcde20e9dfa214d8f9a93de9a
1 /*
2 * This is a module which is used for logging packets to userspace via
3 * nfetlink.
4 *
5 * (C) 2005 by Harald Welte <laforge@netfilter.org>
6 * (C) 2006-2012 Patrick McHardy <kaber@trash.net>
7 *
8 * Based on the old ipv4-only ipt_ULOG.c:
9 * (C) 2000-2004 by Harald Welte <laforge@netfilter.org>
10 *
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License version 2 as
13 * published by the Free Software Foundation.
14 */
15 #include <linux/module.h>
16 #include <linux/skbuff.h>
17 #include <linux/if_arp.h>
18 #include <linux/init.h>
19 #include <linux/ip.h>
20 #include <linux/ipv6.h>
21 #include <linux/netdevice.h>
22 #include <linux/netfilter.h>
23 #include <net/netlink.h>
24 #include <linux/netfilter/nfnetlink.h>
25 #include <linux/netfilter/nfnetlink_log.h>
26 #include <linux/spinlock.h>
27 #include <linux/sysctl.h>
28 #include <linux/proc_fs.h>
29 #include <linux/security.h>
30 #include <linux/list.h>
31 #include <linux/jhash.h>
32 #include <linux/random.h>
33 #include <linux/slab.h>
34 #include <net/sock.h>
35 #include <net/netfilter/nf_log.h>
36 #include <net/netns/generic.h>
37 #include <net/netfilter/nfnetlink_log.h>
38
39 #include <linux/atomic.h>
40
41 #ifdef CONFIG_BRIDGE_NETFILTER
42 #include "../bridge/br_private.h"
43 #endif
44
45 #define NFULNL_NLBUFSIZ_DEFAULT NLMSG_GOODSIZE
46 #define NFULNL_TIMEOUT_DEFAULT 100 /* every second */
47 #define NFULNL_QTHRESH_DEFAULT 100 /* 100 packets */
48 /* max packet size is limited by 16-bit struct nfattr nfa_len field */
49 #define NFULNL_COPY_RANGE_MAX (0xFFFF - NLA_HDRLEN)
50
51 #define PRINTR(x, args...) do { if (net_ratelimit()) \
52 printk(x, ## args); } while (0);
53
54 struct nfulnl_instance {
55 struct hlist_node hlist; /* global list of instances */
56 spinlock_t lock;
57 atomic_t use; /* use count */
58
59 unsigned int qlen; /* number of nlmsgs in skb */
60 struct sk_buff *skb; /* pre-allocatd skb */
61 struct timer_list timer;
62 struct net *net;
63 struct user_namespace *peer_user_ns; /* User namespace of the peer process */
64 int peer_portid; /* PORTID of the peer process */
65
66 /* configurable parameters */
67 unsigned int flushtimeout; /* timeout until queue flush */
68 unsigned int nlbufsiz; /* netlink buffer allocation size */
69 unsigned int qthreshold; /* threshold of the queue */
70 u_int32_t copy_range;
71 u_int32_t seq; /* instance-local sequential counter */
72 u_int16_t group_num; /* number of this queue */
73 u_int16_t flags;
74 u_int8_t copy_mode;
75 struct rcu_head rcu;
76 };
77
78 #define INSTANCE_BUCKETS 16
79 static unsigned int hash_init;
80
81 static int nfnl_log_net_id __read_mostly;
82
83 struct nfnl_log_net {
84 spinlock_t instances_lock;
85 struct hlist_head instance_table[INSTANCE_BUCKETS];
86 atomic_t global_seq;
87 };
88
89 static struct nfnl_log_net *nfnl_log_pernet(struct net *net)
90 {
91 return net_generic(net, nfnl_log_net_id);
92 }
93
94 static inline u_int8_t instance_hashfn(u_int16_t group_num)
95 {
96 return ((group_num & 0xff) % INSTANCE_BUCKETS);
97 }
98
99 static struct nfulnl_instance *
100 __instance_lookup(struct nfnl_log_net *log, u_int16_t group_num)
101 {
102 struct hlist_head *head;
103 struct nfulnl_instance *inst;
104
105 head = &log->instance_table[instance_hashfn(group_num)];
106 hlist_for_each_entry_rcu(inst, head, hlist) {
107 if (inst->group_num == group_num)
108 return inst;
109 }
110 return NULL;
111 }
112
113 static inline void
114 instance_get(struct nfulnl_instance *inst)
115 {
116 atomic_inc(&inst->use);
117 }
118
119 static struct nfulnl_instance *
120 instance_lookup_get(struct nfnl_log_net *log, u_int16_t group_num)
121 {
122 struct nfulnl_instance *inst;
123
124 rcu_read_lock_bh();
125 inst = __instance_lookup(log, group_num);
126 if (inst && !atomic_inc_not_zero(&inst->use))
127 inst = NULL;
128 rcu_read_unlock_bh();
129
130 return inst;
131 }
132
133 static void nfulnl_instance_free_rcu(struct rcu_head *head)
134 {
135 struct nfulnl_instance *inst =
136 container_of(head, struct nfulnl_instance, rcu);
137
138 put_net(inst->net);
139 kfree(inst);
140 module_put(THIS_MODULE);
141 }
142
143 static void
144 instance_put(struct nfulnl_instance *inst)
145 {
146 if (inst && atomic_dec_and_test(&inst->use))
147 call_rcu_bh(&inst->rcu, nfulnl_instance_free_rcu);
148 }
149
150 static void nfulnl_timer(unsigned long data);
151
152 static struct nfulnl_instance *
153 instance_create(struct net *net, u_int16_t group_num,
154 int portid, struct user_namespace *user_ns)
155 {
156 struct nfulnl_instance *inst;
157 struct nfnl_log_net *log = nfnl_log_pernet(net);
158 int err;
159
160 spin_lock_bh(&log->instances_lock);
161 if (__instance_lookup(log, group_num)) {
162 err = -EEXIST;
163 goto out_unlock;
164 }
165
166 inst = kzalloc(sizeof(*inst), GFP_ATOMIC);
167 if (!inst) {
168 err = -ENOMEM;
169 goto out_unlock;
170 }
171
172 if (!try_module_get(THIS_MODULE)) {
173 kfree(inst);
174 err = -EAGAIN;
175 goto out_unlock;
176 }
177
178 INIT_HLIST_NODE(&inst->hlist);
179 spin_lock_init(&inst->lock);
180 /* needs to be two, since we _put() after creation */
181 atomic_set(&inst->use, 2);
182
183 setup_timer(&inst->timer, nfulnl_timer, (unsigned long)inst);
184
185 inst->net = get_net(net);
186 inst->peer_user_ns = user_ns;
187 inst->peer_portid = portid;
188 inst->group_num = group_num;
189
190 inst->qthreshold = NFULNL_QTHRESH_DEFAULT;
191 inst->flushtimeout = NFULNL_TIMEOUT_DEFAULT;
192 inst->nlbufsiz = NFULNL_NLBUFSIZ_DEFAULT;
193 inst->copy_mode = NFULNL_COPY_PACKET;
194 inst->copy_range = NFULNL_COPY_RANGE_MAX;
195
196 hlist_add_head_rcu(&inst->hlist,
197 &log->instance_table[instance_hashfn(group_num)]);
198
199
200 spin_unlock_bh(&log->instances_lock);
201
202 return inst;
203
204 out_unlock:
205 spin_unlock_bh(&log->instances_lock);
206 return ERR_PTR(err);
207 }
208
209 static void __nfulnl_flush(struct nfulnl_instance *inst);
210
211 /* called with BH disabled */
212 static void
213 __instance_destroy(struct nfulnl_instance *inst)
214 {
215 /* first pull it out of the global list */
216 hlist_del_rcu(&inst->hlist);
217
218 /* then flush all pending packets from skb */
219
220 spin_lock(&inst->lock);
221
222 /* lockless readers wont be able to use us */
223 inst->copy_mode = NFULNL_COPY_DISABLED;
224
225 if (inst->skb)
226 __nfulnl_flush(inst);
227 spin_unlock(&inst->lock);
228
229 /* and finally put the refcount */
230 instance_put(inst);
231 }
232
233 static inline void
234 instance_destroy(struct nfnl_log_net *log,
235 struct nfulnl_instance *inst)
236 {
237 spin_lock_bh(&log->instances_lock);
238 __instance_destroy(inst);
239 spin_unlock_bh(&log->instances_lock);
240 }
241
242 static int
243 nfulnl_set_mode(struct nfulnl_instance *inst, u_int8_t mode,
244 unsigned int range)
245 {
246 int status = 0;
247
248 spin_lock_bh(&inst->lock);
249
250 switch (mode) {
251 case NFULNL_COPY_NONE:
252 case NFULNL_COPY_META:
253 inst->copy_mode = mode;
254 inst->copy_range = 0;
255 break;
256
257 case NFULNL_COPY_PACKET:
258 inst->copy_mode = mode;
259 if (range == 0)
260 range = NFULNL_COPY_RANGE_MAX;
261 inst->copy_range = min_t(unsigned int,
262 range, NFULNL_COPY_RANGE_MAX);
263 break;
264
265 default:
266 status = -EINVAL;
267 break;
268 }
269
270 spin_unlock_bh(&inst->lock);
271
272 return status;
273 }
274
275 static int
276 nfulnl_set_nlbufsiz(struct nfulnl_instance *inst, u_int32_t nlbufsiz)
277 {
278 int status;
279
280 spin_lock_bh(&inst->lock);
281 if (nlbufsiz < NFULNL_NLBUFSIZ_DEFAULT)
282 status = -ERANGE;
283 else if (nlbufsiz > 131072)
284 status = -ERANGE;
285 else {
286 inst->nlbufsiz = nlbufsiz;
287 status = 0;
288 }
289 spin_unlock_bh(&inst->lock);
290
291 return status;
292 }
293
294 static int
295 nfulnl_set_timeout(struct nfulnl_instance *inst, u_int32_t timeout)
296 {
297 spin_lock_bh(&inst->lock);
298 inst->flushtimeout = timeout;
299 spin_unlock_bh(&inst->lock);
300
301 return 0;
302 }
303
304 static int
305 nfulnl_set_qthresh(struct nfulnl_instance *inst, u_int32_t qthresh)
306 {
307 spin_lock_bh(&inst->lock);
308 inst->qthreshold = qthresh;
309 spin_unlock_bh(&inst->lock);
310
311 return 0;
312 }
313
314 static int
315 nfulnl_set_flags(struct nfulnl_instance *inst, u_int16_t flags)
316 {
317 spin_lock_bh(&inst->lock);
318 inst->flags = flags;
319 spin_unlock_bh(&inst->lock);
320
321 return 0;
322 }
323
324 static struct sk_buff *
325 nfulnl_alloc_skb(u32 peer_portid, unsigned int inst_size, unsigned int pkt_size)
326 {
327 struct sk_buff *skb;
328 unsigned int n;
329
330 /* alloc skb which should be big enough for a whole multipart
331 * message. WARNING: has to be <= 128k due to slab restrictions */
332
333 n = max(inst_size, pkt_size);
334 skb = nfnetlink_alloc_skb(&init_net, n, peer_portid, GFP_ATOMIC);
335 if (!skb) {
336 if (n > pkt_size) {
337 /* try to allocate only as much as we need for current
338 * packet */
339
340 skb = nfnetlink_alloc_skb(&init_net, pkt_size,
341 peer_portid, GFP_ATOMIC);
342 if (!skb)
343 pr_err("nfnetlink_log: can't even alloc %u bytes\n",
344 pkt_size);
345 }
346 }
347
348 return skb;
349 }
350
351 static void
352 __nfulnl_send(struct nfulnl_instance *inst)
353 {
354 if (inst->qlen > 1) {
355 struct nlmsghdr *nlh = nlmsg_put(inst->skb, 0, 0,
356 NLMSG_DONE,
357 sizeof(struct nfgenmsg),
358 0);
359 if (WARN_ONCE(!nlh, "bad nlskb size: %u, tailroom %d\n",
360 inst->skb->len, skb_tailroom(inst->skb))) {
361 kfree_skb(inst->skb);
362 goto out;
363 }
364 }
365 nfnetlink_unicast(inst->skb, inst->net, inst->peer_portid,
366 MSG_DONTWAIT);
367 out:
368 inst->qlen = 0;
369 inst->skb = NULL;
370 }
371
372 static void
373 __nfulnl_flush(struct nfulnl_instance *inst)
374 {
375 /* timer holds a reference */
376 if (del_timer(&inst->timer))
377 instance_put(inst);
378 if (inst->skb)
379 __nfulnl_send(inst);
380 }
381
382 static void
383 nfulnl_timer(unsigned long data)
384 {
385 struct nfulnl_instance *inst = (struct nfulnl_instance *)data;
386
387 spin_lock_bh(&inst->lock);
388 if (inst->skb)
389 __nfulnl_send(inst);
390 spin_unlock_bh(&inst->lock);
391 instance_put(inst);
392 }
393
394 /* This is an inline function, we don't really care about a long
395 * list of arguments */
396 static inline int
397 __build_packet_message(struct nfnl_log_net *log,
398 struct nfulnl_instance *inst,
399 const struct sk_buff *skb,
400 unsigned int data_len,
401 u_int8_t pf,
402 unsigned int hooknum,
403 const struct net_device *indev,
404 const struct net_device *outdev,
405 const char *prefix, unsigned int plen)
406 {
407 struct nfulnl_msg_packet_hdr pmsg;
408 struct nlmsghdr *nlh;
409 struct nfgenmsg *nfmsg;
410 sk_buff_data_t old_tail = inst->skb->tail;
411 struct sock *sk;
412 const unsigned char *hwhdrp;
413
414 nlh = nlmsg_put(inst->skb, 0, 0,
415 NFNL_SUBSYS_ULOG << 8 | NFULNL_MSG_PACKET,
416 sizeof(struct nfgenmsg), 0);
417 if (!nlh)
418 return -1;
419 nfmsg = nlmsg_data(nlh);
420 nfmsg->nfgen_family = pf;
421 nfmsg->version = NFNETLINK_V0;
422 nfmsg->res_id = htons(inst->group_num);
423
424 memset(&pmsg, 0, sizeof(pmsg));
425 pmsg.hw_protocol = skb->protocol;
426 pmsg.hook = hooknum;
427
428 if (nla_put(inst->skb, NFULA_PACKET_HDR, sizeof(pmsg), &pmsg))
429 goto nla_put_failure;
430
431 if (prefix &&
432 nla_put(inst->skb, NFULA_PREFIX, plen, prefix))
433 goto nla_put_failure;
434
435 if (indev) {
436 #ifndef CONFIG_BRIDGE_NETFILTER
437 if (nla_put_be32(inst->skb, NFULA_IFINDEX_INDEV,
438 htonl(indev->ifindex)))
439 goto nla_put_failure;
440 #else
441 if (pf == PF_BRIDGE) {
442 /* Case 1: outdev is physical input device, we need to
443 * look for bridge group (when called from
444 * netfilter_bridge) */
445 if (nla_put_be32(inst->skb, NFULA_IFINDEX_PHYSINDEV,
446 htonl(indev->ifindex)) ||
447 /* this is the bridge group "brX" */
448 /* rcu_read_lock()ed by nf_hook_slow or nf_log_packet */
449 nla_put_be32(inst->skb, NFULA_IFINDEX_INDEV,
450 htonl(br_port_get_rcu(indev)->br->dev->ifindex)))
451 goto nla_put_failure;
452 } else {
453 /* Case 2: indev is bridge group, we need to look for
454 * physical device (when called from ipv4) */
455 if (nla_put_be32(inst->skb, NFULA_IFINDEX_INDEV,
456 htonl(indev->ifindex)))
457 goto nla_put_failure;
458 if (skb->nf_bridge && skb->nf_bridge->physindev &&
459 nla_put_be32(inst->skb, NFULA_IFINDEX_PHYSINDEV,
460 htonl(skb->nf_bridge->physindev->ifindex)))
461 goto nla_put_failure;
462 }
463 #endif
464 }
465
466 if (outdev) {
467 #ifndef CONFIG_BRIDGE_NETFILTER
468 if (nla_put_be32(inst->skb, NFULA_IFINDEX_OUTDEV,
469 htonl(outdev->ifindex)))
470 goto nla_put_failure;
471 #else
472 if (pf == PF_BRIDGE) {
473 /* Case 1: outdev is physical output device, we need to
474 * look for bridge group (when called from
475 * netfilter_bridge) */
476 if (nla_put_be32(inst->skb, NFULA_IFINDEX_PHYSOUTDEV,
477 htonl(outdev->ifindex)) ||
478 /* this is the bridge group "brX" */
479 /* rcu_read_lock()ed by nf_hook_slow or nf_log_packet */
480 nla_put_be32(inst->skb, NFULA_IFINDEX_OUTDEV,
481 htonl(br_port_get_rcu(outdev)->br->dev->ifindex)))
482 goto nla_put_failure;
483 } else {
484 /* Case 2: indev is a bridge group, we need to look
485 * for physical device (when called from ipv4) */
486 if (nla_put_be32(inst->skb, NFULA_IFINDEX_OUTDEV,
487 htonl(outdev->ifindex)))
488 goto nla_put_failure;
489 if (skb->nf_bridge && skb->nf_bridge->physoutdev &&
490 nla_put_be32(inst->skb, NFULA_IFINDEX_PHYSOUTDEV,
491 htonl(skb->nf_bridge->physoutdev->ifindex)))
492 goto nla_put_failure;
493 }
494 #endif
495 }
496
497 if (skb->mark &&
498 nla_put_be32(inst->skb, NFULA_MARK, htonl(skb->mark)))
499 goto nla_put_failure;
500
501 if (indev && skb->dev &&
502 skb->mac_header != skb->network_header) {
503 struct nfulnl_msg_packet_hw phw;
504 int len;
505
506 memset(&phw, 0, sizeof(phw));
507 len = dev_parse_header(skb, phw.hw_addr);
508 if (len > 0) {
509 phw.hw_addrlen = htons(len);
510 if (nla_put(inst->skb, NFULA_HWADDR, sizeof(phw), &phw))
511 goto nla_put_failure;
512 }
513 }
514
515 if (indev && skb_mac_header_was_set(skb)) {
516 if (nla_put_be16(inst->skb, NFULA_HWTYPE, htons(skb->dev->type)) ||
517 nla_put_be16(inst->skb, NFULA_HWLEN,
518 htons(skb->dev->hard_header_len)))
519 goto nla_put_failure;
520
521 hwhdrp = skb_mac_header(skb);
522
523 if (skb->dev->type == ARPHRD_SIT)
524 hwhdrp -= ETH_HLEN;
525
526 if (hwhdrp >= skb->head &&
527 nla_put(inst->skb, NFULA_HWHEADER,
528 skb->dev->hard_header_len, hwhdrp))
529 goto nla_put_failure;
530 }
531
532 if (skb->tstamp.tv64) {
533 struct nfulnl_msg_packet_timestamp ts;
534 struct timeval tv = ktime_to_timeval(skb->tstamp);
535 ts.sec = cpu_to_be64(tv.tv_sec);
536 ts.usec = cpu_to_be64(tv.tv_usec);
537
538 if (nla_put(inst->skb, NFULA_TIMESTAMP, sizeof(ts), &ts))
539 goto nla_put_failure;
540 }
541
542 /* UID */
543 sk = skb->sk;
544 if (sk && sk->sk_state != TCP_TIME_WAIT) {
545 read_lock_bh(&sk->sk_callback_lock);
546 if (sk->sk_socket && sk->sk_socket->file) {
547 struct file *file = sk->sk_socket->file;
548 const struct cred *cred = file->f_cred;
549 struct user_namespace *user_ns = inst->peer_user_ns;
550 __be32 uid = htonl(from_kuid_munged(user_ns, cred->fsuid));
551 __be32 gid = htonl(from_kgid_munged(user_ns, cred->fsgid));
552 read_unlock_bh(&sk->sk_callback_lock);
553 if (nla_put_be32(inst->skb, NFULA_UID, uid) ||
554 nla_put_be32(inst->skb, NFULA_GID, gid))
555 goto nla_put_failure;
556 } else
557 read_unlock_bh(&sk->sk_callback_lock);
558 }
559
560 /* local sequence number */
561 if ((inst->flags & NFULNL_CFG_F_SEQ) &&
562 nla_put_be32(inst->skb, NFULA_SEQ, htonl(inst->seq++)))
563 goto nla_put_failure;
564
565 /* global sequence number */
566 if ((inst->flags & NFULNL_CFG_F_SEQ_GLOBAL) &&
567 nla_put_be32(inst->skb, NFULA_SEQ_GLOBAL,
568 htonl(atomic_inc_return(&log->global_seq))))
569 goto nla_put_failure;
570
571 if (data_len) {
572 struct nlattr *nla;
573 int size = nla_attr_size(data_len);
574
575 if (skb_tailroom(inst->skb) < nla_total_size(data_len)) {
576 printk(KERN_WARNING "nfnetlink_log: no tailroom!\n");
577 return -1;
578 }
579
580 nla = (struct nlattr *)skb_put(inst->skb, nla_total_size(data_len));
581 nla->nla_type = NFULA_PAYLOAD;
582 nla->nla_len = size;
583
584 if (skb_copy_bits(skb, 0, nla_data(nla), data_len))
585 BUG();
586 }
587
588 nlh->nlmsg_len = inst->skb->tail - old_tail;
589 return 0;
590
591 nla_put_failure:
592 PRINTR(KERN_ERR "nfnetlink_log: error creating log nlmsg\n");
593 return -1;
594 }
595
596 #define RCV_SKB_FAIL(err) do { netlink_ack(skb, nlh, (err)); return; } while (0)
597
598 static struct nf_loginfo default_loginfo = {
599 .type = NF_LOG_TYPE_ULOG,
600 .u = {
601 .ulog = {
602 .copy_len = 0xffff,
603 .group = 0,
604 .qthreshold = 1,
605 },
606 },
607 };
608
609 /* log handler for internal netfilter logging api */
610 void
611 nfulnl_log_packet(struct net *net,
612 u_int8_t pf,
613 unsigned int hooknum,
614 const struct sk_buff *skb,
615 const struct net_device *in,
616 const struct net_device *out,
617 const struct nf_loginfo *li_user,
618 const char *prefix)
619 {
620 unsigned int size, data_len;
621 struct nfulnl_instance *inst;
622 const struct nf_loginfo *li;
623 unsigned int qthreshold;
624 unsigned int plen;
625 struct nfnl_log_net *log = nfnl_log_pernet(net);
626
627 if (li_user && li_user->type == NF_LOG_TYPE_ULOG)
628 li = li_user;
629 else
630 li = &default_loginfo;
631
632 inst = instance_lookup_get(log, li->u.ulog.group);
633 if (!inst)
634 return;
635
636 plen = 0;
637 if (prefix)
638 plen = strlen(prefix) + 1;
639
640 /* FIXME: do we want to make the size calculation conditional based on
641 * what is actually present? way more branches and checks, but more
642 * memory efficient... */
643 size = nlmsg_total_size(sizeof(struct nfgenmsg))
644 + nla_total_size(sizeof(struct nfulnl_msg_packet_hdr))
645 + nla_total_size(sizeof(u_int32_t)) /* ifindex */
646 + nla_total_size(sizeof(u_int32_t)) /* ifindex */
647 #ifdef CONFIG_BRIDGE_NETFILTER
648 + nla_total_size(sizeof(u_int32_t)) /* ifindex */
649 + nla_total_size(sizeof(u_int32_t)) /* ifindex */
650 #endif
651 + nla_total_size(sizeof(u_int32_t)) /* mark */
652 + nla_total_size(sizeof(u_int32_t)) /* uid */
653 + nla_total_size(sizeof(u_int32_t)) /* gid */
654 + nla_total_size(plen) /* prefix */
655 + nla_total_size(sizeof(struct nfulnl_msg_packet_hw))
656 + nla_total_size(sizeof(struct nfulnl_msg_packet_timestamp))
657 + nla_total_size(sizeof(struct nfgenmsg)); /* NLMSG_DONE */
658
659 if (in && skb_mac_header_was_set(skb)) {
660 size += nla_total_size(skb->dev->hard_header_len)
661 + nla_total_size(sizeof(u_int16_t)) /* hwtype */
662 + nla_total_size(sizeof(u_int16_t)); /* hwlen */
663 }
664
665 spin_lock_bh(&inst->lock);
666
667 if (inst->flags & NFULNL_CFG_F_SEQ)
668 size += nla_total_size(sizeof(u_int32_t));
669 if (inst->flags & NFULNL_CFG_F_SEQ_GLOBAL)
670 size += nla_total_size(sizeof(u_int32_t));
671
672 qthreshold = inst->qthreshold;
673 /* per-rule qthreshold overrides per-instance */
674 if (li->u.ulog.qthreshold)
675 if (qthreshold > li->u.ulog.qthreshold)
676 qthreshold = li->u.ulog.qthreshold;
677
678
679 switch (inst->copy_mode) {
680 case NFULNL_COPY_META:
681 case NFULNL_COPY_NONE:
682 data_len = 0;
683 break;
684
685 case NFULNL_COPY_PACKET:
686 if (inst->copy_range > skb->len)
687 data_len = skb->len;
688 else
689 data_len = inst->copy_range;
690
691 size += nla_total_size(data_len);
692 break;
693
694 case NFULNL_COPY_DISABLED:
695 default:
696 goto unlock_and_release;
697 }
698
699 if (inst->skb && size > skb_tailroom(inst->skb)) {
700 /* either the queue len is too high or we don't have
701 * enough room in the skb left. flush to userspace. */
702 __nfulnl_flush(inst);
703 }
704
705 if (!inst->skb) {
706 inst->skb = nfulnl_alloc_skb(inst->peer_portid, inst->nlbufsiz,
707 size);
708 if (!inst->skb)
709 goto alloc_failure;
710 }
711
712 inst->qlen++;
713
714 __build_packet_message(log, inst, skb, data_len, pf,
715 hooknum, in, out, prefix, plen);
716
717 if (inst->qlen >= qthreshold)
718 __nfulnl_flush(inst);
719 /* timer_pending always called within inst->lock, so there
720 * is no chance of a race here */
721 else if (!timer_pending(&inst->timer)) {
722 instance_get(inst);
723 inst->timer.expires = jiffies + (inst->flushtimeout*HZ/100);
724 add_timer(&inst->timer);
725 }
726
727 unlock_and_release:
728 spin_unlock_bh(&inst->lock);
729 instance_put(inst);
730 return;
731
732 alloc_failure:
733 /* FIXME: statistics */
734 goto unlock_and_release;
735 }
736 EXPORT_SYMBOL_GPL(nfulnl_log_packet);
737
738 static int
739 nfulnl_rcv_nl_event(struct notifier_block *this,
740 unsigned long event, void *ptr)
741 {
742 struct netlink_notify *n = ptr;
743 struct nfnl_log_net *log = nfnl_log_pernet(n->net);
744
745 if (event == NETLINK_URELEASE && n->protocol == NETLINK_NETFILTER) {
746 int i;
747
748 /* destroy all instances for this portid */
749 spin_lock_bh(&log->instances_lock);
750 for (i = 0; i < INSTANCE_BUCKETS; i++) {
751 struct hlist_node *t2;
752 struct nfulnl_instance *inst;
753 struct hlist_head *head = &log->instance_table[i];
754
755 hlist_for_each_entry_safe(inst, t2, head, hlist) {
756 if (n->portid == inst->peer_portid)
757 __instance_destroy(inst);
758 }
759 }
760 spin_unlock_bh(&log->instances_lock);
761 }
762 return NOTIFY_DONE;
763 }
764
765 static struct notifier_block nfulnl_rtnl_notifier = {
766 .notifier_call = nfulnl_rcv_nl_event,
767 };
768
769 static int
770 nfulnl_recv_unsupp(struct sock *ctnl, struct sk_buff *skb,
771 const struct nlmsghdr *nlh,
772 const struct nlattr * const nfqa[])
773 {
774 return -ENOTSUPP;
775 }
776
777 static struct nf_logger nfulnl_logger __read_mostly = {
778 .name = "nfnetlink_log",
779 .logfn = &nfulnl_log_packet,
780 .me = THIS_MODULE,
781 };
782
783 static const struct nla_policy nfula_cfg_policy[NFULA_CFG_MAX+1] = {
784 [NFULA_CFG_CMD] = { .len = sizeof(struct nfulnl_msg_config_cmd) },
785 [NFULA_CFG_MODE] = { .len = sizeof(struct nfulnl_msg_config_mode) },
786 [NFULA_CFG_TIMEOUT] = { .type = NLA_U32 },
787 [NFULA_CFG_QTHRESH] = { .type = NLA_U32 },
788 [NFULA_CFG_NLBUFSIZ] = { .type = NLA_U32 },
789 [NFULA_CFG_FLAGS] = { .type = NLA_U16 },
790 };
791
792 static int
793 nfulnl_recv_config(struct sock *ctnl, struct sk_buff *skb,
794 const struct nlmsghdr *nlh,
795 const struct nlattr * const nfula[])
796 {
797 struct nfgenmsg *nfmsg = nlmsg_data(nlh);
798 u_int16_t group_num = ntohs(nfmsg->res_id);
799 struct nfulnl_instance *inst;
800 struct nfulnl_msg_config_cmd *cmd = NULL;
801 struct net *net = sock_net(ctnl);
802 struct nfnl_log_net *log = nfnl_log_pernet(net);
803 int ret = 0;
804
805 if (nfula[NFULA_CFG_CMD]) {
806 u_int8_t pf = nfmsg->nfgen_family;
807 cmd = nla_data(nfula[NFULA_CFG_CMD]);
808
809 /* Commands without queue context */
810 switch (cmd->command) {
811 case NFULNL_CFG_CMD_PF_BIND:
812 return nf_log_bind_pf(net, pf, &nfulnl_logger);
813 case NFULNL_CFG_CMD_PF_UNBIND:
814 nf_log_unbind_pf(net, pf);
815 return 0;
816 }
817 }
818
819 inst = instance_lookup_get(log, group_num);
820 if (inst && inst->peer_portid != NETLINK_CB(skb).portid) {
821 ret = -EPERM;
822 goto out_put;
823 }
824
825 if (cmd != NULL) {
826 switch (cmd->command) {
827 case NFULNL_CFG_CMD_BIND:
828 if (inst) {
829 ret = -EBUSY;
830 goto out_put;
831 }
832
833 inst = instance_create(net, group_num,
834 NETLINK_CB(skb).portid,
835 sk_user_ns(NETLINK_CB(skb).sk));
836 if (IS_ERR(inst)) {
837 ret = PTR_ERR(inst);
838 goto out;
839 }
840 break;
841 case NFULNL_CFG_CMD_UNBIND:
842 if (!inst) {
843 ret = -ENODEV;
844 goto out;
845 }
846
847 instance_destroy(log, inst);
848 goto out_put;
849 default:
850 ret = -ENOTSUPP;
851 break;
852 }
853 }
854
855 if (nfula[NFULA_CFG_MODE]) {
856 struct nfulnl_msg_config_mode *params;
857 params = nla_data(nfula[NFULA_CFG_MODE]);
858
859 if (!inst) {
860 ret = -ENODEV;
861 goto out;
862 }
863 nfulnl_set_mode(inst, params->copy_mode,
864 ntohl(params->copy_range));
865 }
866
867 if (nfula[NFULA_CFG_TIMEOUT]) {
868 __be32 timeout = nla_get_be32(nfula[NFULA_CFG_TIMEOUT]);
869
870 if (!inst) {
871 ret = -ENODEV;
872 goto out;
873 }
874 nfulnl_set_timeout(inst, ntohl(timeout));
875 }
876
877 if (nfula[NFULA_CFG_NLBUFSIZ]) {
878 __be32 nlbufsiz = nla_get_be32(nfula[NFULA_CFG_NLBUFSIZ]);
879
880 if (!inst) {
881 ret = -ENODEV;
882 goto out;
883 }
884 nfulnl_set_nlbufsiz(inst, ntohl(nlbufsiz));
885 }
886
887 if (nfula[NFULA_CFG_QTHRESH]) {
888 __be32 qthresh = nla_get_be32(nfula[NFULA_CFG_QTHRESH]);
889
890 if (!inst) {
891 ret = -ENODEV;
892 goto out;
893 }
894 nfulnl_set_qthresh(inst, ntohl(qthresh));
895 }
896
897 if (nfula[NFULA_CFG_FLAGS]) {
898 __be16 flags = nla_get_be16(nfula[NFULA_CFG_FLAGS]);
899
900 if (!inst) {
901 ret = -ENODEV;
902 goto out;
903 }
904 nfulnl_set_flags(inst, ntohs(flags));
905 }
906
907 out_put:
908 instance_put(inst);
909 out:
910 return ret;
911 }
912
913 static const struct nfnl_callback nfulnl_cb[NFULNL_MSG_MAX] = {
914 [NFULNL_MSG_PACKET] = { .call = nfulnl_recv_unsupp,
915 .attr_count = NFULA_MAX, },
916 [NFULNL_MSG_CONFIG] = { .call = nfulnl_recv_config,
917 .attr_count = NFULA_CFG_MAX,
918 .policy = nfula_cfg_policy },
919 };
920
921 static const struct nfnetlink_subsystem nfulnl_subsys = {
922 .name = "log",
923 .subsys_id = NFNL_SUBSYS_ULOG,
924 .cb_count = NFULNL_MSG_MAX,
925 .cb = nfulnl_cb,
926 };
927
928 #ifdef CONFIG_PROC_FS
929 struct iter_state {
930 struct seq_net_private p;
931 unsigned int bucket;
932 };
933
934 static struct hlist_node *get_first(struct net *net, struct iter_state *st)
935 {
936 struct nfnl_log_net *log;
937 if (!st)
938 return NULL;
939
940 log = nfnl_log_pernet(net);
941
942 for (st->bucket = 0; st->bucket < INSTANCE_BUCKETS; st->bucket++) {
943 struct hlist_head *head = &log->instance_table[st->bucket];
944
945 if (!hlist_empty(head))
946 return rcu_dereference_bh(hlist_first_rcu(head));
947 }
948 return NULL;
949 }
950
951 static struct hlist_node *get_next(struct net *net, struct iter_state *st,
952 struct hlist_node *h)
953 {
954 h = rcu_dereference_bh(hlist_next_rcu(h));
955 while (!h) {
956 struct nfnl_log_net *log;
957 struct hlist_head *head;
958
959 if (++st->bucket >= INSTANCE_BUCKETS)
960 return NULL;
961
962 log = nfnl_log_pernet(net);
963 head = &log->instance_table[st->bucket];
964 h = rcu_dereference_bh(hlist_first_rcu(head));
965 }
966 return h;
967 }
968
969 static struct hlist_node *get_idx(struct net *net, struct iter_state *st,
970 loff_t pos)
971 {
972 struct hlist_node *head;
973 head = get_first(net, st);
974
975 if (head)
976 while (pos && (head = get_next(net, st, head)))
977 pos--;
978 return pos ? NULL : head;
979 }
980
981 static void *seq_start(struct seq_file *s, loff_t *pos)
982 __acquires(rcu_bh)
983 {
984 rcu_read_lock_bh();
985 return get_idx(seq_file_net(s), s->private, *pos);
986 }
987
988 static void *seq_next(struct seq_file *s, void *v, loff_t *pos)
989 {
990 (*pos)++;
991 return get_next(seq_file_net(s), s->private, v);
992 }
993
994 static void seq_stop(struct seq_file *s, void *v)
995 __releases(rcu_bh)
996 {
997 rcu_read_unlock_bh();
998 }
999
1000 static int seq_show(struct seq_file *s, void *v)
1001 {
1002 const struct nfulnl_instance *inst = v;
1003
1004 return seq_printf(s, "%5d %6d %5d %1d %5d %6d %2d\n",
1005 inst->group_num,
1006 inst->peer_portid, inst->qlen,
1007 inst->copy_mode, inst->copy_range,
1008 inst->flushtimeout, atomic_read(&inst->use));
1009 }
1010
1011 static const struct seq_operations nful_seq_ops = {
1012 .start = seq_start,
1013 .next = seq_next,
1014 .stop = seq_stop,
1015 .show = seq_show,
1016 };
1017
1018 static int nful_open(struct inode *inode, struct file *file)
1019 {
1020 return seq_open_net(inode, file, &nful_seq_ops,
1021 sizeof(struct iter_state));
1022 }
1023
1024 static const struct file_operations nful_file_ops = {
1025 .owner = THIS_MODULE,
1026 .open = nful_open,
1027 .read = seq_read,
1028 .llseek = seq_lseek,
1029 .release = seq_release_net,
1030 };
1031
1032 #endif /* PROC_FS */
1033
1034 static int __net_init nfnl_log_net_init(struct net *net)
1035 {
1036 unsigned int i;
1037 struct nfnl_log_net *log = nfnl_log_pernet(net);
1038
1039 for (i = 0; i < INSTANCE_BUCKETS; i++)
1040 INIT_HLIST_HEAD(&log->instance_table[i]);
1041 spin_lock_init(&log->instances_lock);
1042
1043 #ifdef CONFIG_PROC_FS
1044 if (!proc_create("nfnetlink_log", 0440,
1045 net->nf.proc_netfilter, &nful_file_ops))
1046 return -ENOMEM;
1047 #endif
1048 return 0;
1049 }
1050
1051 static void __net_exit nfnl_log_net_exit(struct net *net)
1052 {
1053 #ifdef CONFIG_PROC_FS
1054 remove_proc_entry("nfnetlink_log", net->nf.proc_netfilter);
1055 #endif
1056 }
1057
1058 static struct pernet_operations nfnl_log_net_ops = {
1059 .init = nfnl_log_net_init,
1060 .exit = nfnl_log_net_exit,
1061 .id = &nfnl_log_net_id,
1062 .size = sizeof(struct nfnl_log_net),
1063 };
1064
1065 static int __init nfnetlink_log_init(void)
1066 {
1067 int status = -ENOMEM;
1068
1069 /* it's not really all that important to have a random value, so
1070 * we can do this from the init function, even if there hasn't
1071 * been that much entropy yet */
1072 get_random_bytes(&hash_init, sizeof(hash_init));
1073
1074 netlink_register_notifier(&nfulnl_rtnl_notifier);
1075 status = nfnetlink_subsys_register(&nfulnl_subsys);
1076 if (status < 0) {
1077 pr_err("log: failed to create netlink socket\n");
1078 goto cleanup_netlink_notifier;
1079 }
1080
1081 status = nf_log_register(NFPROTO_UNSPEC, &nfulnl_logger);
1082 if (status < 0) {
1083 pr_err("log: failed to register logger\n");
1084 goto cleanup_subsys;
1085 }
1086
1087 status = register_pernet_subsys(&nfnl_log_net_ops);
1088 if (status < 0) {
1089 pr_err("log: failed to register pernet ops\n");
1090 goto cleanup_logger;
1091 }
1092 return status;
1093
1094 cleanup_logger:
1095 nf_log_unregister(&nfulnl_logger);
1096 cleanup_subsys:
1097 nfnetlink_subsys_unregister(&nfulnl_subsys);
1098 cleanup_netlink_notifier:
1099 netlink_unregister_notifier(&nfulnl_rtnl_notifier);
1100 return status;
1101 }
1102
1103 static void __exit nfnetlink_log_fini(void)
1104 {
1105 unregister_pernet_subsys(&nfnl_log_net_ops);
1106 nf_log_unregister(&nfulnl_logger);
1107 nfnetlink_subsys_unregister(&nfulnl_subsys);
1108 netlink_unregister_notifier(&nfulnl_rtnl_notifier);
1109 }
1110
1111 MODULE_DESCRIPTION("netfilter userspace logging");
1112 MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
1113 MODULE_LICENSE("GPL");
1114 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_ULOG);
1115
1116 module_init(nfnetlink_log_init);
1117 module_exit(nfnetlink_log_fini);
Linux with added FPC-III support